Semi-automatic b-b pistol with trigger-connnected linkages

ABSTRACT

In this pistol an operating pin on the trigger is connected by a linkage to the hammer, and by a lever to a cylindrical loader that pivots at the inner end of the barrel between loading and firing positions respectively. The trigger is spring-loaded to its released position. In this position the loader is in loading position in which a duct therethrough will receive a BB projectile from the magazine. When the trigger is pulled, the loader is pivoted to swing the duct therethrough and the BB therein into registry both with a gas inlet port and the bore of the barrel and the hammer is tripped to open the valve which supplies the propellant gas to the duct and the ball is propelled from the barrel.

United States Patent 1191 Crane et al.

11 1 f 3,824,981 1451' July 23, 1974 [75] Inventors: James W. Crane, Fairport; David R.

Hand, Newark, both of NY.

[73] Assignee: Crosman Arms Company, Inc.,

Fairport, NY.

[22] Filed: Dec. 13, 1972 [21] Appl. No.: 314,761

[52] US. Cl 124/11 R, 124/53, 124/40 7/1960 Webby 124/11 R 2/1963 Kline et al 124/11 R Primary ExaminerRichard C. Pinkham Assistant Examiner-Richard T. Stouffer Attorney, Agent, or FirmShlesinger, Fitzsimmons & Shlesinger [57] ABSTRACT In this pistol an operating pin on the trigger is connected By a linkage to the hammer, and by a lever to a cylindrical loader that pivots at the inner end of the [51] Int CL F41, 11/06 barrel between loading and firing positions respec- [58] Field A 50 51 R tively. The trigger is spring-loaded to its released posi- 1 tion. In this position the loader is in loading position in which a duct therethrough will receive a BB projectile [56] References Cited from the magazine. When the trigger is pulled, the loader is pivoted to swing the duct therethrough and UNITED STATES PATENTS the BB therein into registry both with a gas inlet port s y 2 and the bore of the barrel and the hammer is tripped 1 to open the valve which supplies the propellant gas to 1,292,665 1/1919 Udesen 124/13 A 1,516,483 11/1924 Krafft mm A the duct and the ban propelled from the barrel 2,699,767 1/1955 Mangolini 124/11 R Claims, 6 Drawing Figures +3 I! I /l0 1 r 1 24 K 1 H 2 38 l1 1\ \f/ 37 x s 2 45 59 it x 52 58 i 1 4 O 13 14 15 46 7: 42'40 1 Yb 1 44 I l 44 59,60 53 :6 +3 j 8 10 3 63 12 s 7 --48 all? 0 52 +6 113 49 1 SEMI-AUTOMATIC B-B PISTOL WITH TRIGGER-CONNNECTED LINKAGES This invention relates to pistols, and more particularly to a semi-automatic gas-operated B-B pistol.

One disadvantage of conventional B-B pistols of the semi-automatic variety is that a rather complex mechanism has been required heretofore to effect the loading of a new B-B projectile into firing position in the pistol each time it is fired. Prior such mechanisms have added undesirably to the overall cost of the pistol, and have not been completely satisfactory in operation.

It is an object of the invention to provide an improved semi-automatic B-B pistol that is substantially more reliable and inexpensive than prior pistols.

Another object of this invention is to provide for a B-B pistol of the type described a novel loading linkage,

which is operable to load and fire the pistol successively in response to operation of the pistol trigger.

Still a further object of this invention is to provide for a pistol of the type described a relatively simple and compact loading and firing mechanism, which is substantially more compact and reliable than prior such mechanisms.

Other objects of the invention will be apparent hereinafter from the specification and from the recital of the appended claims, particularly when read in conjunction with the accompanying drawings.

In the drawings: i

FIG. 1 is a fragmentary side elevational view of agasoperated B-B pistol made in accordance with one embodiment of this invention, portions of the pistol being cut away and shown in section;

FIG. 2 is a fragmentary sectional view taken along the line 2--2 in FIG. 1 looking in the direction of the arrows;

FIG. 3 is a fragmentary sectional view taken along the line 33 in FIG. 1 looking in the direction of the arrows;

FIG. 4 is a fragmentary sectional view taken along the line 44 in FIG. 1 looking in the direction of the arrows;

FIG. 5 is a sectional view taken along a line 55 in FIG. 1 looking in the direction of the arrows; and

FIG. 6 is a sectional view taken along the line 66 in FIG. 1 looking in the direction of the arrows.

Referring now to the drawings by numerals of refer ence, 10 denotes generally a B-B pistol comprising a hollow frame ,11 having an integral, downwardly depending hand grip l2, and a forwardly projecting barrel section 13, which surrounds a tubular gun barrel 14 (FIG. 1). Barrel 14 is secured at its forward end in section 13 by a setscrew l5, and at its rear end in a valve block 18, as by a pressed fit. Block 18 is secured in frame 11 above the hand grip 12.

Hand grip 12 is hollow and is adapted to hold a cylinder or cartridge of compressed gas, such as CO which supplies the power for propelling BBs from the gun.

Mounted to reciprocate in a cylindrical bore or magazine 20 (FIG. 1), which is formed in section 13 above and parallel to the barrel 14, is a conventional, springpressed follower 21. Adjacent its outer or forward end follower 21 has the usual operating pin 22, which projects radially outwardly through an elongate slot 23 that communicates with bore 20 and that is formed in one side of frame section 13 to allow manual movement of the follower 21 against the resistance of spring 24, to permit the magazine to be loaded through port 25 in the top of section 13. At its inner end follower 21 is slidable at least part-way into bore 28, which is formed in valve block 18.

Mounted to pivot in a transverse bore formed in valve block 18 at right angles to the axis of barrel 14 is a cylindrical loader 32 (FIGS. 1, 2 and 4). Loader 32 has therethrough a diametral bore 34, which, for the major part of its length, is slightly smaller in diameter than a BB projectile. At one end, however, bore 34 is slightly enlarged as denoted at 35 (FIG. 1), to provide a pocket for holding a single B-B. Normally pocket 35 is disposed in registry with the rear end of bore 28 to receive a B-B projectile from the magazine 20, but when the pistol is fired, as described hereinafter, loader 32 is pivoted to a firing position in which pocket 35 registers with the rear end of the bore of barrel 14.

Block 18 also contains a right-angular gas supply duct 37 having its upper portion 38, opening on loader 30 so that whenever loader 32 is pivoted to firing position the portion 38 of duct 37 will register with bore 34 in the loader.

When the cartridge C has been punctured, gas therefrom enters, through a duct (not shown) into a chamber 40, formed in block 18 and in communication with the lower end of duct 37. Chamber 40 is provided with a valve seat 41. A spring-loaded valve 42 in chamber 40 normally is urged by a spring 43, to closed position in which it is seated against the valve seat 41 to prevent gas in the chamber 40 from entering duct 37. Valve 42 has a reduced-diameterstem 44, which slides in valve block 18 and projects at its rear end out of this block.

A hammer 45 (FIGS. 1 to 3) is mounted adjacent its lower end in frame 11 to pivot about a pin 46, which extends between opposite sides of the frame 11 rearwardly of block 18, and parallel to the axis of rotation of the loader 32. A spring 48 (FIG. 1), which is connected at one end to hammer 45 and at its opposite end to a pin 49 in grip l2, urges hammer 45 into engagement with the rear end of the valve stem 44. Normally, however, the force exerted by the spring 48 on the hammer 45 is not sufficient to overcome the tension exerted by the spring 43 on the valve 42, so that normally valve 43 remains in its closed position to prevent escape of gas under pressure from chamber 40 into duct Mounted at its upper end to pivot on a pin 50, which extends transversely between opposite sides of the frame 13 forwardly of valve block 18, is a trigger 51 (FIGS. 1, 2 and 5). The lower end of the trigger projects downwardly into the usual trigger guard 52. Intermediate its ends trigger 51 carries a pair of spaced pins 52 and 53. The loader 32 is connected to trigger 51 by a single link 54, which is pivotally connected at one end by the pin 52 to the trigger at one side thereof, and at its opposite end by a pin 55 (FIGS. 2 and 4), to a crankarm 56 (FIGS. 1 and 4), which is integral with loader 32.

Trigger 51 is connected to hammer 45 by links 58 and 59 (FIGS. 1, 2, 5 and 6). Link 58 is pivotally mounted intermediate its ends by pin 52 on the opposite side of the trigger from link 54; and link 59 (FIGS. 1 to 4) is pivotally connected by pin 60 to the rear of link 58, and by pin 61 to hammer 45 above the hammer pivot 46. Adjacent its forward end lever 59 is connected by a tension spring 63 to a stationary pin 64 dis- 3 posed in the grip 12 downwardly and rearwardly of the trigger. Spring 63 urges links 58 and 59 downwardly to a collapsed position (full lines in FIG. 1) in which the underside of link 58 engages pin 53 to urge trigger 51 forwardly toward its released position. In this position loader 32 is held in projectile loading position through operation of pin 52 and link 54. In this position springs 63 and 48 hold hammer 45 in its upright or released posmon.

Assuming that there are B-Bs in the magazine and that the pocket 38in the loader 32 contains a 8-8 as shown in FIG. 1, and assuming also that the cartridge C has been punctured so that CO gas under pressure has entered the chamber 40, the pistol can be fired merely by pulling the trigger 51 rearwardly to its broken line position (FIG. 1). During this movement pins 52 and 53 are swung by the trigger slightly clockwise about the axis of the trigger pivot pin 50 to second limit positions. Pin 52 thereby causes link 54 to be shifted rearwardly far enough to swing the loader 32 into its firing position in which its bore 34 registers with the barrel l4, and pin 53 simultaneously causes link 58 to be swung clockwise (FIG. 1) about the axis of pin 50 so that pin 60 and link 59 are forced upwardly. During this movement link 59 first swings hammer 45 slightly 1 counterclockwise (FIG. 1) about the axis of pin 46 against the resistance of spring 48; but as soon as pin 60 passes above an imaginary plane containing the axes of pins 52 and 61, spring 48 causes the links 58 and 59 to snap suddenly upwardly to their released or broken line positions in FIG. 1.' This causes the hammer 45 suddenly to pivot forwardly to strike the valve stem 44 with sufficient force to open the valve 42. Gas under pressure from chamber 40 then flows through duct 37 and loader bore 34 to the rear of the projectile in pocket 35, causing this projectile to be propelled out of the bore of the barrel l4. Momentarily after the valve 42 has been opened, the spring 43 returns the valve to closed position.

Upon the release of the trigger, spring 63draws links 58 and 59 downwardly, and through pin 53 urges trigger 51 forwardly and counterclockwise (FIG. 1) about the axis of pin 50 back to its full line position. During the advance of trigger 51 and pin 52 the link 54 is also drawn forwardly to its original ,or released position, thereby causing loader 32 to be swung back to its loading position in which its pocket 35 registers with bore 28 in valve block 18 to receive another B-B or projectile from the magazine 20.

Mounted to slide on the trigger guard 52 forwardly of the trigger 51 is a safety 70; The safety comprises a plate 71 mounted to reciprocate parallel to the barrel 14 in registering grooves formed in opposite sides of the frame section 13 as shown in FIG. 6. The plate has a downwardly projecting skirt portion 72, which overlies a recess 74 in the trigger guard in which a springloaded detent 73 is housed. Ball detent 73 is urged resiliently into, one of two notches or openings 75 in the skirt to hold the safety releasably in either its operative or its inoperative position. On its left or rear end as illustrated in FIG. 1, the plate 71 has an upwardly projecting tang 76, which is registrable with a notch 78 formed in the underside of link 58 adjacent its forward end, when the safety has been shifted rearwardly of frame section 13 to engage therein and prevent trigger 51 from being pivoted to firingposition.

From the foregoing it will be apparent that the instant invention produces an extremely simple and reliable means for simultaneously loading and firing a gasoperated B-B pistol. Unlike most conventional pistols which employ a sear for operating the hammer, the hammer of the hereindescribed pistol is manipulated by a linkage, which is always positively connected to the hammer 45, but which imparts motion to the hammer only when the linkage pin 60 is moved upwardly by the trigger 51. This eliminates much of the wear that is prevalent in conventional pistols of the type in which the sear pin slidably engages and disengages the associated hammer to effect operation thereof. Moreover, the hammer operating linkage and the loader operating link 54 are both manipulated through the same pin 52, which is carried by the trigger. With this construction the timing of the movements of the loader 32 and hammer 45 can be very accurately determined and controlled, and there is minimal wear in the moving parts. Additionally, the reciprocable safety provides relatively simple means for securing the trigger 51 and link 58 against accidental movement, whenthe pistol is not in use.

While the invention has been describedin connection with a specific embodiment thereof, it will be understood that it is capable of further modification; and this application is intended to cover any modifications that come within the disclosure or the limits of the appended claims.

Having thusdescribed our invention, what we claim 1s:

1. A gas-operated gun, comprising a frame containing a projectile magazine and a supply of gas under pressure,

a barrel secured in said frame,

a projectile loader mounted in said frame for move- 1 ment in opposite directions between a loading position in which it receives a projectile from said magazine', and a firing position in which it holds the projectile in registry with the bore of said barrel, said loader having a duct therethrough for conducting gas from said supply to the rear of a projectile contained in said loader,

means including a normally-closed valve for preventing flow of the gas from said supply to said duct,

and operative, when said valve is open and said loader is in its firing position, to deliver gas from said supply through said duct to the rear of the projectile to propel it out of said loader and through said barrel,

a hammer mounted on said frame for movement from an inactive into a firing position in which it momentarily opens said valve,

a trigger movable on said frame between firing and released positions,

a linkage positively connecting said trigger to said loader to shift said loader positively from its loading to its firing position upon movement of said trigger to its firing position, and

a linkage positively connecting said trigger to said hammer and operative, each time said trigger is moved to its firing position, to move said hammer positively into cocked position, and

spring means operative, upon movement of said hammer to cocked position, to drive said hammer to firing position, to open said valve when said loader is in its firing position.

2. A gas-operated gun, comprising a frame containing a projectile magazine and a supply of gas under pressure,

a barrel secured in said frame,

a projectile loader mounted in said frame for movement in opposite directions between a loading position in which it receives a projectile from said magazine, and a firing position in which it holds the projectile in registry with the bore of said barrel,

means including a normally-closed valve for preventing flow of the gas from said supply to said loader, and operative, when said valve is open and said loader is in its firing position, to deliver gas from said supply to the rear of the projectile to propel it out of said barrel,

a hammer mounted on said frame for movement from inactive into firing position in which it momentarily opens said valve,

a trigger movable on said frame between firing and released positions,

means connecting said trigger to said loader to shift said loader from its loading to its firing position upon movement of said trigger to its firing position, and

means also connecting said trigger to said hammer and operative, each time said trigger is moved to its firing position momentarily to move said hammer into its firing position to open said valve when said loader is in its firing position,

said last-named means comprising a first link pivotally connected by a first pin to said trigger,

a second link pivotally connected at one end by a second pin to said first link and at its opposite end by a third pin to said hammer, and resilient means normally urging said hammer toward its firing position.

3. A gas-operated gun as claimed in claim 2, wherein said resilient means normally holds said links in a first position in which said second pin is positioned at one side of an imaginary plane containing the axes of said first and third pins,

said trigger is operative during movement thereof to its firing position to swing said first pin and said first link in a direction to shift said second pin to the opposite side of said plane, and

said resilient means is operative, when said second pin has been shifted to said opposite side of said plane, suddenly to urge said hammer to its firing position, thereby to open said valve.

4. A gas-operated gun, comprising a frame containing a projectile magazine and a supply of gas under pressure,

a barrel secured in said frame,

a projectile loader mounted in said frame for movement in opposite directions between a loading position in which it receives a projectile from said magazine, and a firing position in which it holds the projectile in registry with the bore of said barrel,

means including a normally-closed valve for preventing flow of the gas from said supply to said loader, and operative, when said valve is open and said loader is in its firing position, to deliver gas from said supply to the rear of the projectile to propel it out of said barrel,

a hammer mounted on said frame for movement from inactive into firing position in which it momentarily opens said valve,

a trigger movable on said frame between firing and released positions,

means connecting said trigger to said loader to shift said loader from its loading to its firing position upon movement of said trigger to its firing position, and

means also connecting said trigger to said hammer and operative, each time said trigger is moved to its firing position, momentarily to move said hammer positively into its firing position to open said valve when said loader is in its firing position, said hammer and trigger being mounted to pivot about spaced, parallel axes,

resilient means constantly urging said hammer to its firing position, and

said means connecting said trigger to said hammer comprising a pair of pivotally interconnected links movable from a first to a second position during movement of said trigger from its released to its firing position, and vice versa,

said links being operative during initial movement thereof from said first to said second position to pivot said hammer against the resistance of said resilient means, and

said resilient means being operative after predetermined movement of said links from said first to said second position suddenly to urge said links rapidly to said second position while urging said hammer rapidly back to its firing position.

5. ,A gas-operated gun as defined in claim 4, wherein said loader is mounted to pivot between loading and firing positions about an axis parallel to the pivotal axes of said hammer and trigger, and

said means connecting said trigger to said loader comprises a third link pivotally connected at one end to said trigger and at its opposite end to said loader thereby to pivot said loader in response to pivotal movement of said trigger.

6. A gas-operated gun as defined in claim 5, wherein one of said pair of links is pivotally connected at one end to said hammer,

the other of said pair of links is pivotally connected at one end to the opposite end of said one link, and is pivotally connected intermediate its ends to said trigger, and

said other link and said one end of said third link pivot about a common axis that extends through said trigger parallel to the pivotal axis thereof.

7. A gas-operated gun as defined in claim 6, wherein the opposite end of said other link is disposed to be swung in an arcuate path upon pivotal movement of said trigger, and

a safety member is mounted on said frame adjacent said trigger for manual movement into and out of an operative position in which said member projects into said path to prevent movement of said other link and said trigger.

8. A gas-operated gun, comprising a frame having therein a projectile magazine and a supply of gas under pressure,

zine,

a cylindrical projectile loader rotatably mounted in said frame rearwardly of said barrel to pivot about neously to pivot said hammer about its pivotal axis to cocked position, each time said trigger is moved from its released to its fired position, and

8 loading position in which a projectile pocket in said loader registers with said magazine, and a firing position in which said pocket and the projectile therein register with the rear end of said bore,

an axis perpendicular to the bore of said barrel bea hammer mounted on said frame rearwardly of said tween a loading position in which a projectile barrel to pivot from inoperative to firing position pocket in said loader registers with said magazine, about an axis parallel to the axis of rotation of said and a firing position in which said pocket and the loader, projectile therein register with the rear end of said means including a normally closed valve positioned bore, said loader having a duct therein for conduct- 10 to be opened by said hammer each time the latter ing gas from said supply to the rear of a projectile is pivoted to firing position, and operative, when in said loader, said valve is open and said loader is in its firing poa hammer mounted on said frame rearwardly of said sition, to convey gas under pressure from said supbarrel to pivot from cocked to firing position about ply to the rear of the projectile in said pocket to an axis parallel to the axis of rotation of said loader, propel the projectile out of said barrel,

a trigger pivoted on said frame for movement bemeans including a normally closed valve positioned tween released and fired positions, respectively, to be opened by said hammer each time the latter about an axis parallel to the first-named axes, and is pivoted to firing position, and operative, when said valve is open and said loader is in its firing pomeans connecting said trigger to said hammer and to sition, to convey gas under pressure from said supsaid loader to move said loader from its loading to ply to the rear of the projectile in said pocket to its firing position, and simultaneously to pivot said propel the projectile out of said barrel, hammer about its pivotal axis to firing position, a trigger pivoted on said frame for movement beeach time said trigger is moved from its released to tween released and fired positions, respectively, its fired position, I about an axis parallel to the first-named axes, and said connecting means comprising a first rigid link I pivotally connected at one end to said trigger and linkage positively connecting said trigger to said at its opposite end to said loader to impart the pivhammer and to said loader to move said loader otal movement of said trigger to said loader, and from its loading to its firing position, and simultaa pair of collapsible links pivotally connected at opposite ends to said trigger and said hammer, respectively, and having adjacent ends pivotally connected to each other by a pin that is swingable, durspring means operative, upon movement of said hammer to cocked position, to fire said hammer. 9. A gas-operated gun as defined in claim 8, wherein said connecting means comprises a first linkage for imparting the pivotal movement of said trigger to said loader, and

ing pivotal movement of said trigger between its released and firing positions, between limit positions from one side to the other of a plane containing the pivotal axes of said opposite ends of said links, and

resilient means connected to said hammer to resist a second linkage for imparting to said hammer the 40 movement of said hammer and pin, during initial pivotal movement to its cocked position. movement of said trigger from its released to its 10. A gas-operated gun comprising fired position, and operative, when said pin has a frame having therein a projectile magazine and a swung beyond said plane toward said other side I supply of gas under pressure, thereof, suddenly to snap said pin to its other limit a barrel mounted in said frame adjacent said magaposition, and said hammer from its inoperative to zine, its firing position, thereby momentarily to open a cylindrical projectile loader mounted in said frame said valve. inoperative to its firing position, thereby rearwardly of said barrel to pivot about an axis permomentarily to open said valve. pendicular to the bore of said barrel between a 

1. A gas-operated gun, comprising a frame containing a projectile magazine and a supply of gas under pressure, a barrel secured in said frame, a projectile loader mounted in said frame for movement in opposite directions between a loading position in which it receives a projectile from said magazine, and a firing position in which it holds the projectile in registry with the bore of said barrel, said loader having a duct therethrough for conducting gas from said supply to the rear of a projectile contained in said loader, means including a normally-closed valve for preventing flow of the gas from said supply to said duct, and operative, when said valve is open and said loader is in its firing position, to deliver gas from said supply through said duct to the rear of the projectile to propel it out of said loader and through said barrel, a hammer mounted on said frame for movement from an inactive into a firing position in which it momentarily opens said valve, a trigger movable on said frame between firing and released positions, a linkage positively connecting said trigger to said loader to shift said loader positively from its loading to its firing position upon movement of said trigger to its firing position, and a linkage positively connecting said trigger to said hammer and operative, each time said trigger is moved to its firing position, to move said hammer positively into cocked position, and spring means operative, upon movement of said hammer to cocked position, to drive said hammer to firing position, to open said valve when said loader is in its firing position.
 2. A gas-operated gun, comprising a frame containing a projectile magazine and a supply of gas under pressure, a barrel secured in said frame, a projectile loader mounted in said frame for movement in opposite directions between a loading position in which it receives a projectile from said magazine, and a firing position in which it holds the projectile in registry with the bore of said barrel, means including a normally-closed valve for preventing flow of the gas from said supply to said loader, and operative, when said valve is open and said loader is in its firing position, to deliver gas from said supply to the rear of the projectile to propel it out of said barrel, a hammer mounted on said frame for movement from inactive into firing position in which it momentarily opens said valve, a trigger movable on said frame between firing and released positions, means connecting said trigger to said loader to shift said loader from its loading to its firing position upon movement of said trigger to its firing position, and means also connecting said trigger to said hammer and operative, each time said trigger is moved to its firing pOsition momentarily to move said hammer into its firing position to open said valve when said loader is in its firing position, said last-named means comprising a first link pivotally connected by a first pin to said trigger, a second link pivotally connected at one end by a second pin to said first link and at its opposite end by a third pin to said hammer, and resilient means normally urging said hammer toward its firing position.
 3. A gas-operated gun as claimed in claim 2, wherein said resilient means normally holds said links in a first position in which said second pin is positioned at one side of an imaginary plane containing the axes of said first and third pins, said trigger is operative during movement thereof to its firing position to swing said first pin and said first link in a direction to shift said second pin to the opposite side of said plane, and said resilient means is operative, when said second pin has been shifted to said opposite side of said plane, suddenly to urge said hammer to its firing position, thereby to open said valve.
 4. A gas-operated gun, comprising a frame containing a projectile magazine and a supply of gas under pressure, a barrel secured in said frame, a projectile loader mounted in said frame for movement in opposite directions between a loading position in which it receives a projectile from said magazine, and a firing position in which it holds the projectile in registry with the bore of said barrel, means including a normally-closed valve for preventing flow of the gas from said supply to said loader, and operative, when said valve is open and said loader is in its firing position, to deliver gas from said supply to the rear of the projectile to propel it out of said barrel, a hammer mounted on said frame for movement from inactive into firing position in which it momentarily opens said valve, a trigger movable on said frame between firing and released positions, means connecting said trigger to said loader to shift said loader from its loading to its firing position upon movement of said trigger to its firing position, and means also connecting said trigger to said hammer and operative, each time said trigger is moved to its firing position, momentarily to move said hammer positively into its firing position to open said valve when said loader is in its firing position, said hammer and trigger being mounted to pivot about spaced, parallel axes, resilient means constantly urging said hammer to its firing position, and said means connecting said trigger to said hammer comprising a pair of pivotally interconnected links movable from a first to a second position during movement of said trigger from its released to its firing position, and vice versa, said links being operative during initial movement thereof from said first to said second position to pivot said hammer against the resistance of said resilient means, and said resilient means being operative after predetermined movement of said links from said first to said second position suddenly to urge said links rapidly to said second position while urging said hammer rapidly back to its firing position.
 5. A gas-operated gun as defined in claim 4, wherein said loader is mounted to pivot between loading and firing positions about an axis parallel to the pivotal axes of said hammer and trigger, and said means connecting said trigger to said loader comprises a third link pivotally connected at one end to said trigger and at its opposite end to said loader thereby to pivot said loader in response to pivotal movement of said trigger.
 6. A gas-operated gun as defined in claim 5, wherein one of said pair of links is pivotally connected at one end to said hammer, the other of said pair of links is pivotally connected at one end to the opposite end of said one link, and is pivotally connected intermediate its ends to said trigger, and said other link and saId one end of said third link pivot about a common axis that extends through said trigger parallel to the pivotal axis thereof.
 7. A gas-operated gun as defined in claim 6, wherein the opposite end of said other link is disposed to be swung in an arcuate path upon pivotal movement of said trigger, and a safety member is mounted on said frame adjacent said trigger for manual movement into and out of an operative position in which said member projects into said path to prevent movement of said other link and said trigger.
 8. A gas-operated gun, comprising a frame having therein a projectile magazine and a supply of gas under pressure, a barrel mounted in said frame adjacent said magazine, a cylindrical projectile loader rotatably mounted in said frame rearwardly of said barrel to pivot about an axis perpendicular to the bore of said barrel between a loading position in which a projectile pocket in said loader registers with said magazine, and a firing position in which said pocket and the projectile therein register with the rear end of said bore, said loader having a duct therein for conducting gas from said supply to the rear of a projectile in said loader, a hammer mounted on said frame rearwardly of said barrel to pivot from cocked to firing position about an axis parallel to the axis of rotation of said loader, means including a normally closed valve positioned to be opened by said hammer each time the latter is pivoted to firing position, and operative, when said valve is open and said loader is in its firing position, to convey gas under pressure from said supply to the rear of the projectile in said pocket to propel the projectile out of said barrel, a trigger pivoted on said frame for movement between released and fired positions, respectively, about an axis parallel to the first-named axes, and linkage positively connecting said trigger to said hammer and to said loader to move said loader from its loading to its firing position, and simultaneously to pivot said hammer about its pivotal axis to cocked position, each time said trigger is moved from its released to its fired position, and spring means operative, upon movement of said hammer to cocked position, to fire said hammer.
 9. A gas-operated gun as defined in claim 8, wherein said connecting means comprises a first linkage for imparting the pivotal movement of said trigger to said loader, and a second linkage for imparting to said hammer the pivotal movement to its cocked position.
 10. A gas-operated gun comprising a frame having therein a projectile magazine and a supply of gas under pressure, a barrel mounted in said frame adjacent said magazine, a cylindrical projectile loader mounted in said frame rearwardly of said barrel to pivot about an axis perpendicular to the bore of said barrel between a loading position in which a projectile pocket in said loader registers with said magazine, and a firing position in which said pocket and the projectile therein register with the rear end of said bore, a hammer mounted on said frame rearwardly of said barrel to pivot from inoperative to firing position about an axis parallel to the axis of rotation of said loader, means including a normally closed valve positioned to be opened by said hammer each time the latter is pivoted to firing position, and operative, when said valve is open and said loader is in its firing position, to convey gas under pressure from said supply to the rear of the projectile in said pocket to propel the projectile out of said barrel, a trigger pivoted on said frame for movement between released and fired positions, respectively, about an axis parallel to the first-named axes, and means connecting said trigger to said hammer and to said loader to move said loader from its loading to its firing position, and simultaneously to pivot said hammer about its pivotal axis to firing position, each time said trigger is moved from its released to its fired position, said connecting means comprising a first rigid link pivotally connected at one end to said trigger and at its opposite end to said loader to impart the pivotal movement of said trigger to said loader, and a pair of collapsible links pivotally connected at opposite ends to said trigger and said hammer, respectively, and having adjacent ends pivotally connected to each other by a pin that is swingable, during pivotal movement of said trigger between its released and firing positions, between limit positions from one side to the other of a plane containing the pivotal axes of said opposite ends of said links, and resilient means connected to said hammer to resist movement of said hammer and pin, during initial movement of said trigger from its released to its fired position, and operative, when said pin has swung beyond said plane toward said other side thereof, suddenly to snap said pin to its other limit position, and said hammer from its inoperative to its firing position, thereby momentarily to open said valve. inoperative to its firing position, thereby momentarily to open said valve. 